Navigation Dropdowns and Slideshow

I am using a Twenty-Twelve child theme and the WP-Cycle Plus Captions plug-in.

My Problem: the dropdown menu goes behind the slideshow on my homepage.

I have searched through these forums and have found answers related to the problem I am having, but they address specific plug-ins and themes.

They all say you need to raise the z-index of the navigation bar.
I have tried this but am having no success.

Maybe I am not doing it in the right place?

Can someone please help me? Let me know if you need any additional info.

Here is the link to the site (it’s a school project): https://www.amandahaslipdesigns.com/proj1/

The “Films” section is the only one with a drop down so far.